1. Field of the Invention
The invention relates in general to cooling systems, and more particularly to an adaptive cooling control system for use primarily in association with cooling operating fluids of heavy construction equipment. The invention is not however limited thereto, and may be adapted for use in association with the cooling systems of different equipment and machinery.
2. Background Art
The use of cooling systems for internal combustion engines and the like has long been known in the art. The engine and transmission are cooled by the circulation of fluids. Such fluids generally include engine coolant, oil, transmission fluid, steering fluid, and hydraulic fluid, among others. Generally, fans are used to cool heat exchangers (radiators) which carry the various fluids. The fans can be operated in many different manners, such as through an electric motor, a hydraulic motor or the fan may be driven directly by the engine crankshaft.
While these solutions have proved successful, they do have certain drawbacks. For example, electric fans generally place large loads upon the alternator and are rather expensive solutions. Fans driven by the crankshaft are in constant rotation--even when not needed--rendering them inefficient. Furthermore, in certain cold climates, with a directly driven fan the operating fluids may not even reach the proper elevated operating temperatures.
To solve such problems, variable speed fans have been utilized. Such fans have been powered by hydraulic pumps associated with the engine. In particular, the pump that rotates with the crankshaft powers the fan motor. Such a solution, while an improvement over the above-identified solutions, nevertheless suffers from certain drawbacks. For example, since pump speed is directly associated with engine speed, such fans include continuously variable thermostatic control devices to control the speed of the fan independently from the speed of the engine and pump. As a result these complex systems require frequent maintenance and are quite expensive to produce and maintain.
It is therefore an object of the invention to provide an improved control system for a hydraulic cooling fan that overcomes the shortcomings of the prior art.
It is another object of the invention to provide a control system which can utilize commercially available components so as to enhance durability and to minimize cost.
These and other objects of the invention will become apparent in light of the specification and claims appended hereto.